基于9个叶绿体基因片段(atpA、atpB、matK、petA、psaA、psbA、psbB、psbC和rbcL), 深入探讨了稻属(Oryza)3个BBCC基因组异源四倍体和5个与之相关的BB或CC基因组二倍体物种间的谱系关系。进一步的系统发育分析表明: 3个具有相同BBCC基因组的四倍体物种并非同一次物种形成事件的产物, 而是在不同的分布区经历了至少3次分别的物种起源。其中, 四倍体Oryza punctata的母本可能来自同样分布在非洲并具有CC基因组的二倍体物种O. eichingeri; 而四倍体O. malampuzhaensis和O. minuta的母本则可能来自亚洲已经灭绝的具有BB基因组的不同二倍体。研究结果不但为追溯稻属异源四倍体的复杂网状进化提供了重要的分子证据, 而且拓展了我们对有花植物复杂物种形成的深入理解。

With 9 maternal heritable chloroplast gene fragments (atpA, atpB, matK, petA, psaA, psbA, psbB, psbC, and rbcL), we explored the lineage relationships of 3 BBCC genome allotetraploids and 5 related BB or CC genome diploids in the Oryza genus. Further phylogenetic analyses indicated that the 3 allotetraploid species did not originate from a common speciation event but occurred at least 3 times in different distribution areas. The maternal parent of the tetraploid O. punctata was possibly the Africa CC genome diploid O. eichingeri, whereas the maternal parent of O. minuta and O. malampuzhaensis was possibly 2 extinct Asian BB genome diploids. Our results provided important molecular evidence to track complicated reticular evolutionary processes for the polyploids and also broaden our understanding of the puzzling speciation histories of flowering plants.